We owe our ability to get lunch from a can to the rise of Napoleon. We call it canned food. It's a common kitchen shelf presence: food in a tin can. Actually, that particular term is derived from the description "tinned canister" common in the early 1800's when canned foods were developed. What we think of as a tin can is actually tinplate, made of tin-plated steel. Other metals can be used as with aluminum in canned soda or beer.

During the Napoleonic Wars, the French Army found itself in need of a way of transporting food. It was, after all, Napoleon who recognized the need to care for this most basic of a soldier's needs when he famously observed "an army marches on its stomach."

In 1795, Europe was embroiled in war. Soldiers needed to be fed, sailors were developing scurvy at sea. A prize was offered for a solution, a prize claimed by Nicolas Appert in 1809 who received 12,000 francs.

Discovery

Using crude means with glass jars and corks, Appert discovered he could heat-sterilize the food in the container and seal the container hermetically. The result was preserved, edible food. The principle remains at the basis of canning today.

Tin Cans

Further research showed that tin cans were preferable alternative to the glass jars and bottles Appert began with and began manufacturing them himself. That aspect of the process was less successful, not to take away the credit he's due for discovering the benefits of the canning process.

Actually, it was an Englishman, Peter Durand, (He stole the idea from the French guy! ) who took the next step. Durand patented a tin plate canister in 1810. The result looked much like the can on the shelf at today's local Kroger store, except that Durand's were handmade.

With shears and tinsnips, a tinsmith cut an oblong piece from a sheet of tinned iron sheeting, curved the piece around on itself and soldered the edges together. He then cut out a round piece and soldered it to the bottom of the resulting canister. Another round piece was soldered on top once the can was filled with its edible contents. A small hole was left in the top piece so the can be boiled without exploding due to the expanding contents. With the can still hot, the hole was soldered closed.

The use of tin solder could be harmful. In 1845, the Arctic expedition of Sir John Franklin after three years of eating canned food has crew members suffering from the effects of severe lead poisoning.

Military veterans who remember canned C-rations with the ham and beans or spaghetti, sometimes heated in a trash barrel full of boiling water, sometimes unpalatably cold, can trace their canned meals directly to the British Army. It was in 1813, the first commercial canning factory opened in England, under license from Appert, manufacturing canned food under contract for the army.

English-born William Underwood established a successful New England canning business, starting with bottles and in 1839 switching to tin cans. One of his tinkers could turn out 60 tin cans a day.

That changed in 1846 when a machine was invented by Henry Evans that could turn out ten times Underwood's output, 60 cans an hour.

In 1858, with the metal in tin cans thinning down, the first can opener appeared. It would come into common use during the approaching American Civil War.

Canned Food in the Civil War

In 1861, Fort Sumter was bombarded. Troops were recruited, and they needed feeding. They needed canned foods.

Demand provided the tune for an intricate dance of technological innovations that gradually transformed the industry in a 50-60 year period starting with the Civil War.

In 1861, a Baltimore canner, adapting an English discovery, found that the addition of calcium chloride to the boiling water raised the temperature to above 240 degrees drastically reducing the sterilization process from five or six hours to a half hour.

At the beginning of the Civil War, about 5 million cans were being turned out. By 1870, that figure was up to 30 million.

Civil war soldiers were eating from tin cans, sailors on Naval ships ate from tin cans, hospital patients ate meals featuring fresh foods from cans, small town and rural Americans began seeing canned vegetables normally unavailable to them on their shelves.

Improvements Continue

There were refinements in canning machinery that further simplified the production process, such as capping seals, a furnace that allowed sealing of cans much faster than a tinsmith.

Product improvement was also ongoing. In 1866, a tin can was patented which had a key attached to it, such as you still find with sardine cans. Sanitary cans were introduced in 1896, produced by chemist Charles M. Ams, which permitted an open-top can, easier to fill than the hole-in-top can it replaced.

After 10 years of attempts, Borden began to develop a market for its canned condensed milk. Corn, peas, and tomatoes began finding their way into cans, as did pineapples, salmon, apples, pears, and other edibles.

All benefited from production improvements in their own fields which dovetailed nicely with the increasing availability to producers of constantly improving canning techniques. The result was that canned food reached people in greater and greater amounts, creating a huge new market.

By shortly after the turn of the century, as portrayed in the movie Big Jake, John Wayne is offering to share canned peaches with Richard Boone who declines, saying they hurt his teeth.

But it wasn't just peaches and other fruit and vegetables that found their way into cans. In 1935, the first canned beer appeared and that soon became a major force in the market. In 1959, another refinement appeared, aimed primarily at beverages: the pop-top can.

All of which traces back to Napoleon's need to keep his Army fed as it swarmed over Europe.

I have eaten 10 year old home canned moose meat and it was great. It has been several years since I had moose meat, but I have eaten 5 year old home canned salmon on several occasions with no ill effects. As long as the lid isn't rusty inside, I would be good with eating any meat up to 10 years old that I had personally canned myself.